This invention relates to a mask blank substrate, a mask blank, an exposure mask, a mask blank substrate manufacturing method, and a semiconductor manufacturing method.
Various proposals have been made for methods each for selecting a mask substrate that is excellent in flatness after having been chucked on a mask stage of an exposure system (see, e.g. JP-A-2003-50458).
However, according to the conventional methods, with respect to each of a plurality of mask substrates (mask blank substrates), it is necessary to acquire information indicative of the surface shape of the main surface and information indicative of flatness of the main surface before and after chucking on the mask stage of the exposure system or acquire information indicative of flatness of the main surface through simulation where the flatness of the main surface after setting in the exposure system is derived based on the flatness of the main surface before the setting and a structure of a mask chuck of the exposure system. Therefore, much time and labor have been required for selecting a mask substrate that is excellent in flatness after having been chucked by the mask stage of the exposure system.